Southern Counties Veterinary Specialists, Anaesthesia Department, Ringwood, UK.
Southern Counties Veterinary Specialists, Anaesthesia Department, Ringwood, UK.
Vet Anaesth Analg. 2022 Jan;49(1):76-84. doi: 10.1016/j.vaa.2021.06.017. Epub 2021 Sep 9.
To assess the accuracy and trending capability of continuous measurement of haemoglobin concentration [Hb], haemoglobin oxygen saturation (SaO) and oxygen content (CaO) measured by the Masimo Radical-7 pulse co-oximeter in horses undergoing inhalational anaesthesia.
Prospective observational clinical study.
A group of 23 anaesthetized adult horses.
In 23 healthy adult horses undergoing elective surgical procedures, paired measurements of pulse co-oximetry-based haemoglobin concentration (SpHb), SaO (SpO), and CaO (SpOC) and simultaneous arterial blood samples were collected at multiple time points throughout anaesthesia. The arterial samples were analysed by a laboratory co-oximeter for total haemoglobin (tHb), SaO and manually calculated CaO. Bland-Altman plots, linear regression analysis, error grid analysis, four-quadrant plot and Critchley polar plot were used to assess the accuracy and trending capability of the pulse co-oximeter. Data are presented as mean differences and 95% limits of agreement (LoA).
In 101 data pairs analysed, the pulse co-oximeter slightly underestimated tHb (bias 0.06 g dL; LoA -1.0 to 1.2 g dL), SaO (bias 1.4%; LoA -2.0% to 4.8%), and CaO (bias 0.3 mL dL; LoA -2.1 to 2.7 mL dL). Zone A of the error grid encompassed 99% of data pairs for SpHb. Perfusion index (PI) ≥ 1% was recorded in 58/101 and PI < 1% in 43/101. The concordance rate for consecutive changes in SpHb and tHb with PI ≥ 1% and < 1% was 80% and 91% with four-quadrant plot, and 45.8% and 66.6% with Critchley polar plot.
Pulse co-oximetry has acceptable accuracy for the values measured, even with low PI, whereas its trending ability requires further investigation in those horses with a higher [Hb] variation during anaesthesia.
评估 Masimo Radical-7 脉搏血氧饱和度仪连续测量血红蛋白浓度[Hb]、血红蛋白氧饱和度（SaO）和氧含量（CaO）在吸入麻醉马匹中的准确性和趋势能力。
前瞻性观察性临床研究。
一组 23 头麻醉成年马。
在 23 头接受择期手术的健康成年马中，在麻醉过程中的多个时间点采集脉搏血氧饱和度仪测量的血红蛋白浓度（SpHb）、SaO（SpO）和 CaO（SpOC）的配对测量值和同时的动脉血样。动脉血样由实验室血氧仪分析总血红蛋白（tHb）、SaO 和手动计算的 CaO。 Bland-Altman 图、线性回归分析、误差网格分析、四象限图和 Critchley 极坐标图用于评估脉搏血氧饱和度仪的准确性和趋势能力。数据以均值差和 95%一致性界限（LoA）表示。
在分析的 101 对数据中，脉搏血氧饱和度仪略微低估了 tHb（偏差 0.06 g dL；LoA -1.0 至 1.2 g dL）、SaO（偏差 1.4%；LoA -2.0%至 4.8%）和 CaO（偏差 0.3 mL dL；LoA -2.1 至 2.7 mL dL）。SpHb 的误差网格 A 区包含 99%的数据对。58/101 次记录 PI≥1%，43/101 次记录 PI<1%。PI≥1%和<1%时 SpHb 和 tHb 连续变化的一致性率分别为 80%和 91%（四象限图）和 45.8%和 66.6%（Critchley 极坐标图）。
即使 PI 较低，脉搏血氧饱和度仪的测量值也具有可接受的准确性，但其趋势能力需要在麻醉期间[Hb]变化较大的马匹中进一步研究。
